Notifications represent a key element in smart devices. In fact, a device could be considered {\textquoteleft}{\textquoteleft}smart{\textquoteright}{\textquoteright} if it is able to provide different type of messages or notifications to the users. In this way, people who use smart devices receive a significant number of notifications daily. However, how many notifications can a user receive and attend daily? If the number of notifications increases a lot, it is possible that the user experience decrease. In this article, a study is carried out on the level of user{\textquoteright}s satisfaction related to the number of notifications received in different smart devices. To achieve this goal, a survey was applied taking into consideration the following devices: smart speaker, smart fridge, smart TV, smart watch, smart phone, and car{\textquoteright}s integrated computer system. The study comprises the participation of 439 people from 8 countries.